Motive-fluid-operated tool.



No. 692,388. Patented Feb. 4, I902.

H. H. VAUGHAN.

MDTIVE FLUID OPERATED TOOL.

(Application filed. Apr. 5, 1901.) (No Model.) 2 sheetssheet I.

No. 692,388. Patented Feb. 4, I902.

H. H. VAUGHAN.

MOTIVE FLUID-OPERATED TOOL.

(Application fl1d Aprv 5, 1901.) (No Model.) 2 Shoots-Sheet 2.

PATENT OFFICE.

HENRY H. VAUGHAN, OF CHICAGO, ILLINOIS, ASSIGNOR TO RIDGELY AND JOHNSON TOOL COMPANY, A CORPORATION OF ILLINOIS.

MOTIVE-FLUlD-OPER-ATED TOOL.

SPECIFICATION forming part of Letters Patent No. 692,388, dated February 4, 1902. Application filed April 5, 1901. Serial No. 5 1,440. (No model.)

To all whom, it may concern:

Be it known that I, HENRY I-I. VAUGHAN, a citizen of the United States, residing at Ohicago, in the county of Cook, State of Illinois, have invented certain new and useful Improvements in Motive-Fl uid-Operated Tools; and Ihereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, in which- Figure 1 is a view of a pneumatic hammer embodying myinvention, the cylinder and reducing-sleeve being in section and the piston in elevation, the ports or passages of the piston being indicated in dotted lines. Figs. 2, 3, and 4 are transverse sections on the lines 2 2, 3 3, and 4 4, respectively. Fig. 5 is a modification,the cylinderand red ucing-sleeve being shown in longitudinal central section and the piston in elevation, with the passages and ports thereof in dotted lines.

Like symbols refer to like parts wherever they occur.

My invention relates to the construction of that class of motive-fluid-operated tools commonly termed pneumatic hammers, and it consists, generally stated, in the combination, with a suitable cylinder having motivefluid-supply ports and passages and an exhaust-port or exhaust-ports, of a differential piston having a stem through which extends the exhaust passage and port or ports for the under side of the piston or for that head of the piston having the greater area, whereby the exhaust is carried to the back or handle end of the tool and may be allowed to escape thereat.

There are other minor features of invention, all as will hereinafter more fully appear.

I will now proceed to describe my invention more fully, so that others skilled in the art to which it appertains may apply the same.

In the drawings, 1 indicates the cylinder, and 2 the differential piston, of a pneumatic hammer provided with a suitable handle A and a lever-operated valve B, which controls the supply-passage a, leading to the cylinder 1. This handle may terminate in an internally-threaded sleeve 8, which receives the externallythreaded end of the cylinder 1, and is prevented from rotation by a paw1-andratchet device 1), as shown in the drawings, or any other suitable method of connecting the handle to the cylinder may be adopted at the will of the constructor.

In the present instance the differential piston is one wherein the area of one head of the piston is reduced by a stem 2, which extends back into a stem chamber or portion of the cylinder having a reduced diameter and which is provided with an exhaust-port or ex haust-ports l, the motive fluid operating on the shoulder 2 (the lesser head of the piston) to deliver the working blow.

The internal diameterofcylinderlbetween the points a a or for the travel of the piston corresponds in diameter with the diameter of the piston 2, while below said portion, as from b b, it is provided with an enlarged diameter or clearance-space for the piston, and above said portion, as from c c, it is reduced in diameter to correspond with the diameter of the stem 2 of the piston.

In the Walls of the cylinder 1 and leading from the motive-fluid-supply passage 0. are a series of supply-passages 3 8, leading to that part of the cylinder which contains the lesser head of the piston or shoulder 2 formed by the union of the stem 2 with the piston 2, and leading therefrom to that portion of the cyl- 8o inder which contains the greater head of the piston (or head having the greater area) are a further series of supply-passages 4 4.

As a matter of construction I prefer to reduce the internal diameter of the cylinder to form a stem-chamber for thereception of the stem 2 of the piston by means of an inserted reducing-sleeve 5, grooved on its exterior to form the supply-passages 3, which sleeve or stem-chamber is closed at one end and held 0 in place by the handle A or the equivalent thereof. The internal diameter of said reducing-sleeve 5 at that end which receives the piston-stem 2 corresponds with said stem; but above the same or next to the handle the 5 internal diameter of said sleeve 5 is increased or equivalent provision for clearance for the end of stem 2 is made for purposes which will hereinafter appear.

Extending lengthwise of the stem 2 and into the piston 2 is a passage 6, which communicates with the greater head of the piston by ports or passages 6 and with the periphery of the piston-stem 2 at its opposite or handle end by means of ports or passages 6",

6 6 being exhaust-pasthe said passages 6 the passages 6 6 6 of the piston 2 and its stem 2", which lead to the exhaust-ports 1, are used as exhaust-passages only.

' In the modification shown in Fig. 5, however, the supply-passage 4 of the cylinder, which leads through the cylinder from the lesser to the greater head of the piston, has

been omitted and the inserted reductionsleeve 5 shortened, so that the ports or passages 6" of the stem can open both into the stem-chamber and into the cylinder opposite the shoulder 2" or lesser head of the piston, and thus the stem-ports will act not only as exhaust-passages for the greater head of the piston, but also as supply-passages in lieu of the passages t of the preferred form.

The construction being substantially such as hereinbefore set forth, the operation of the devices will be as follows: The blow of the piston or hammer 2 having been delivered upon the snap or tool stem S and the parts being in the position shown in the drawings, in the case of the preferred construction shown in Fig. 1 the motive-fluid supply will pass from supply-passage 3 into the cylinder and thence by supply-passages 4 to that head of the piston having the greater area, and as the ports or passages 6 at the handle end of stem 2 are closed by the walls of the cylinder or inserted sleeve 5 the piston 2 will be reversed or lifted for its working stroke and will travel back until the ports 6 of the stem enter the clearance-space in sleeve 5, when exhaust will at once take place through exhaust-ports 1*, and the supply-passages tfor the greater head of the piston having been closed by the travel of the piston the pressure upon shoulder 2 (the lesser head of the piston) being constant in the direction of the tool will reverse the piston and deliver-the hammer-blow thereof at the same time that the walls of the cylinder close the exhaustpassages through the stem 2.

In the case of the modification shown in Fig. 4 of the drawings, where the supply-passages are omitted and the sleeve 5 shortened, the ports 6 of the stem will when the hammer-blow has been delivered by the pressure of the motive fluid on the shoulder 2" stand open to the motive-fluid supply in the cylinder above the lesser piston-head or shoulder 2", and the motive fluid will pass through the ports and passages of the stem .2 to that head of the piston having the greater area, after which the lift of the piston will cut off the motive-fluid pressure to the greater head of the piston, but its movement will continue by expansion until the exhaust-port 6 of the ceases stem is opened, after which, the pressure being constant on the shoulder 2 and in the direction of the tool, the devices will operate as hereinbefore set forth, the ports and passages 6, 6*, and 6 of the stem becoming exhaust ports and passages as soon as the port 6 is uncovered by the wall of the cylinder or sleeve 5, as before stated, the exhaust in both constructions taking place through the stem and at the back or handle end of the cylinder.

Having thus described my invention, what I claim, and desire to secure by Letters Pat ent, is

1. In amotive-tluid-operated tool, the combination with a cylinder having suitable supply-ports, and an exhaust-port, of adifferential piston having an exhaust-passage therethrough which connects the greater head of the piston with the exhaust-port of the cylinder, the exhaust and supply ports being arranged to maintain a constant pressure on the lesser head of the piston and in the direction of the tool; substantially as and for the purposes specified.

2. In a motive-fiuid-operated tool, the combination with a cylinder havingsupply-ports, and an exhaust port orpassage, of a difierential piston provided with a stem having an exhaust-passage which communicates with the exhaust-port of the cylinder and with the greater head of the piston, the exhaust and supply ports being arranged to maintain a constant pressure on the lesser head of the piston and in the direction of the tool; substantially as and for the purposes specified.

3. In a motive-fluid-operated tool, the combination with a cylinder having supply-ports, of a piston having a stem on its lesser head, said stem provided with exhaust-passages which open on the periphery of the stem, and an exhaust-port opening from the chamber which receives the stem of the piston, the exhaust and supply ports being arranged to maintain a constant pressure on the lesser head of the piston and in the direction of the tool; substantially as and for the purposes specified.

4. In a motive-fiuid-operated tool, the combination with a cylinder having a supply-port and a chamber for the reception of the stem of a piston, said chamber provided with an exhaust, of a piston having a stem provided with an exhaust-port leading from the greater head of the piston and delivering into the stem-chamber, the exhaust and supply ports being arranged to maintain a constant pressure on the lesser head of the piston and in the direction of the tool; substantially as and for the purposes specified.

In testimony whereof I affix my signature, in presence of two witnesses, this 2d day of April, 1901.

HENRY II. VAUGHAN. WVitnesses:

FRED KIRGIS, GEORGE I. McELDoWNEY. 

